
A relaxation of the above definition is to maintain that only the output and not the meta-data satisfy the above condition i.e. \((S^{\prime }) = (\mathbf {A}(S),S^{\prime }\backslash S \cup S\backslash S^{\prime },S)\) . However, we will work with the stronger notion. This, with a slight difference, is referred to as perfect unlearning in [1]}.

Even though the above definition is for one edit request, it can be generalized for a stream of \(k\)  edit requests, by having that this condition holds inductively for every point in the stream.

